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51.
A pilot‐scale trial to rear fat snook Centropomus parallelus through larval, weaning and nursery phases was conducted in Florianópolis, Brazil. Eggs (96% fertilization) from captive broodstock, induced to spawn using 50 μg/kg LHRHa were stocked in two 4,000‐L cylindrical fiberglass tanks at a mean density of 19.2 eggs/L. Nannochloropsis oculata was stocked with the eggs and maintained at a mean density of 0.5–1.0 ± 106 cells/mL up to 31 dph (31 dph). Hatching averaged 90%. Larvae were fed rotifers Brachionus rotundiformis enriched with an oil emulsion from 3 dph to 36 dph (30–40 rotifers/mL) and Artermia meta‐nauplii enriched with Selco from 22 dph to 60 dph (mean 2.9 meta‐nauplii/mL). Weaning began at 45 dph with an artificial dry diet NRG (50% protein), supplied together with concentrated and enriched Artemia meta‐nauplii. No critical period of mortality was observed during larval rearing. During the 43 days of weaning and nursery, less than 1% mortality was recorded. Food conversion rate during nursery was 1.17, with a change in the coefficient of variation of mean total length of 1.3%. Specific total growth rate in weight was 13.0 %/d and mean growth in total length and total weight were 0.65 mm/d and 24.0 mg/d over the whole rearing trial respectively. Mean total length and total weight of juveniles were 57.6 ± 0.1 mm and 2.11 ± 0.12 g, respectively, and the length‐weight relationship was W = 8.29931 ± 10–5 TL3.049607 (r= 0.9986). on 88 dph when the trial was terminated. The condition factor on 88 dph was 1.104. On 88 dph a total of 35,000 juveniles were harvested, overall survival was 25.5% with mean final density of 4.4 fishn and biomass of 6.9 kg/m3. The present trial demonstrated the feasibility of mass production of fat snook. Possible improvements necessary for commercial cultivation of fat snook C. parallelus are discussed.  相似文献   
52.
Use of domestic reference values in the flow cytometry analysis is known to improve its accuracy by integrating local variations as gender, race and age. Up to date application of flow cytometry in veterinary medicine has been limited to describe the percentual values just for peripheral lymphocytes subsets of blood. We now report establishment of reference values for a wide range of proportional and absolute numbers of peripheral blood leukocytes, including T cells subsets, B cells, monocytes and eosinophils, applicable to the healthy population of Beagles in Brazil and other regions with similar demographic characteristics. Normal reference values were also established to estimate the gender-related differences. This information will provide clinical aid in the evaluation of immunologic status as well as standard values for experimental animals of dogs from Brazil and other similar regions.  相似文献   
53.
Isolation and identification of goose parvovirus in the UK   总被引:2,自引:0,他引:2  
  相似文献   
54.
In cabbage, glucosinolates such as sinigrin are hydrolyzed by plant myrosinase to allyl isothiocyanate (AITC), allyl cyanide, and, in the presence of an epithiospecifier protein, 1-cyano-2,3-epithiopropane (CEP). Isothiocyanates have been implicated in the cancer-protective effects of Brassica vegetables. The effect of processing on the hydrolysis of glucosinolates was investigated in cabbage. Cabbage was steamed or microwaved for six time durations over 7 min. Glucosinolate concentrations were slightly reduced after microwave cooking (P < 0.001) but were not influenced after steaming (P < 0.05). Myrosinase activity was effectively lost after 2 min of microwave cooking and after 7 min of steaming. Hydrolysis of residual glucosinolates following cooking yielded predominantly CEP at short cooking durations and AITC at longer durations until myrosinase activity was lost. Lightly cooked cabbage produced the highest yield of AITC on hydrolysis in vitro, suggesting that cooking Brassica vegetables for a relatively short duration may be desirable from a health perspective.  相似文献   
55.
A 5-year-old female Holstein cow was examined for ocular discharge, periorbital swelling, an area of full-thickness corneal cellular infiltrate, fibrin, hypopyon, diffuse corneal edema, and miosis. The patient was diagnosed with a corneal stromal abscess and secondary anterior uveitis. Histopathology, mycotic culture, and polymerase chain reaction positive for Aspergillus and Fusarium DNA confirmed the presence of fungal infection. Response to therapy was adequate, and follow-up with the patient 1 year after diagnosis revealed a focal area of corneal fibrosis.  相似文献   
56.
Meloidogyne incognita is one of the most polyphagous species of root-knot nematodes occurring in Brazil and worldwide. Eight M. incognita isolates were studied, representing two enzymatic phenotypes (esterase and malate desydrogenase: I1/N1, I2/N1) and four cryptic Meloidogyne sp.1 (S2/N1) isolates, representing one cytological type (3n?=?40–46). Three M. hispanica isolates (Hi3/N1, 2n?=?32–36) and two of an atypical Meloidogyne sp.2 (S2a/N3, 3n?=?40–44) were included in this study for comparison. All isolates were tested with three M. incognita-specific molecular markers. The primer pairs B06F/R, miF/R and incK14F/R amplified three species-specific fragments of 1,200?bp, 955?bp and 399?bp, respectively for M. incognita and Meloidogyne sp.1 isolates. No amplification occurred in the M. hispanica and Meloidogyne sp.2 isolates, except with primers miF/R (1,650?bp). The genetic variability of the Meloidogyne spp. isolates was evaluated, using RAPD and ISSR markers. The phylogenetic analyses revealed two strongly supported monophyletic clades: clade I, consisting of M. hispanica and the atypical Meloidogyne sp.2 isolates, and clade II, clustering together all M. incognita and the Meloidogyne sp.1 isolates. Considering the biometrical, cytological and molecular approaches, it was possible to conclude that the isolates with three enzymatic phenotypes (I1/N1, I2/N1 and S2/N1) presented the characteristics described for M. incognita. Some correlations were detected between the isozymatic phenotypes and the tree topology (S2a/N3, Hi3/N1, I1/N1, S2/N1), but no strict correlation could be observed for the phenotype I2/N1 and one isolate of S2/N1. Morphologically, the Msp.2 isolates differ from M. incognita and M. hispanica by the female stylet features presenting straight cone tip and round pear shaped knobs, posteriorly sloping. The results of this study suggested that the Msp.2 isolates with phenotypes S2aN3 belong to a new or an unidentified species closely related to M. hispanica.  相似文献   
57.
Supermassive black holes (SMBHs; mass is greater than or approximately 10(5) times that of the Sun) are known to exist at the center of most galaxies with sufficient stellar mass. In the local universe, it is possible to infer their properties from the surrounding stars or gas. However, at high redshifts we require active, continuous accretion to infer the presence of the SMBHs, which often comes in the form of long-term accretion in active galactic nuclei. SMBHs can also capture and tidally disrupt stars orbiting nearby, resulting in bright flares from otherwise quiescent black holes. Here, we report on a ~200-second x-ray quasi-periodicity around a previously dormant SMBH located in the center of a galaxy at redshift z = 0.3534. This result may open the possibility of probing general relativity beyond our local universe.  相似文献   
58.

Background

Porcine circovirus type 2 (PCV2) has been associated with several disease complexes, including reproductive failure. The aim of this study was to identify the subtypes of PCV2 that are associated with reproductive failure in pigs from the State of São Paulo, Brazil and to investigate co-infections with other infectious organisms.

Findings

Samples of 168 aborted foetuses or mummified foetuses from five farrow-to-finish swine farms known to be infected with PCV2 and located in the State of São Paulo were tested for PCV2 by polymerase chain reaction (PCR). Positive samples were additionally tested for porcine parvovirus (PPV), Leptospira spp. and Brucella spp. by PCR. PCV2 was detected in 18 of the samples (10.7%). PPV, Brucella spp. and Leptospira spp were found in 2, 10 and 0 cases, respectively. Eleven PCV2 strains were sequenced and determined to be either genotype 2a (n = 1) or 2b (n = 10).

Conclusions

The findings indicate that the frequency of PCV2 infections in aborted porcine foetuses from the State of São Paulo is rather low (10.7%) and that co-infection with other pathogens is common and may be involved in PCV2 associated reproductive failure. No repeatable, characteristic amino acid motifs for regions of the PCV2 capsid protein seemed to be associated with abortion in sows.  相似文献   
59.
A spinal cord lesion localised caudal to the L6 spinal segment was diagnosed in a 2-year-old female spayed domestic longhair cat with acute onset paraparesis. Magnetic resonance imaging findings were consistent with an acute, non-compressive nucleus pulposus extrusion of the L5-L6 intervertebral disc. The cat was successfully managed with supportive care, including cage confinement.  相似文献   
60.
ObjectiveTo evaluate the effects of a constant rate infusion (CRI) of lidocaine alone or in combination with ketamine on the minimum infusion rate (MIR) of propofol in dogs and to compare the hemodynamic effects produced by propofol, propofol-lidocaine or propofol-lidocaine-ketamine anesthesia.Study designProspective, randomized cross-over experimental design.AnimalsFourteen adult mixed-breed dogs weighing 15.8 ± 3.5 kg.MethodsEight dogs were anesthetized on different occasions to determine the MIR of propofol alone and propofol in combination with lidocaine (loading dose [LD] 1.5 mg kg?1, CRI 0.25 mg kg?1 minute?1) or lidocaine (LD 1.5 mg kg?1, CRI 0.25 mg kg?1 minute?1) and ketamine (LD 1 mg kg?1, CRI 0.1 mg kg?1 minute?1). In six other dogs, the hemodynamic effects and bispectral index (BIS) were investigated. Each animal received each treatment (propofol, propofol-lidocaine or propofol-lidocaine-ketamine) on the basis of the MIR of propofol determined in the first set of experiments.ResultsMean ± SD MIR of propofol was 0.51 ± 0.08 mg kg?1 minute?1. Lidocaine-ketamine significantly decreased the MIR of propofol to 0.31 ± 0.07 mg kg?1 minute?1 (37 ± 18% reduction), although lidocaine alone did not (0.42 ± 0.08 mg kg?1 minute?1, 18 ± 7% reduction). Hemodynamic effects were similar in all treatments. Compared with the conscious state, in all treatments, heart rate, cardiac index, mean arterial blood pressure, stroke index and oxygen delivery index decreased significantly, whereas systemic vascular resistance index increased. Stroke index was lower in dogs treated with propofol-lidocaine-ketamine at 30 minutes compared with propofol alone. The BIS was lower during anesthesia with propofol-lidocaine-ketamine compared to propofol alone.Conclusions and clinical relevanceLidocaine-ketamine, but not lidocaine alone, reduced the MIR of propofol in dogs. Neither lidocaine nor lidocaine in combination with ketamine attenuated cardiovascular depression produced by a continuous rate infusion of propofol.  相似文献   
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